K&K make an external pre-amp with EQ for the Pure Mini, correct impedance and great sound. But if you have EQ on your amp, or can trust your sound-man with EQ on the PA, a pre-amp's unnecessary - just use an active DI (such as the Orchid) which has an input impedance of 1 Megohm, the K&K Pure Mini puts out a very hot signal, and makes a pre-amp unnecessary in most circumstances.